Reversible variable volume pump



June 8, 1965 P. HARTMANN 3,187,676

REVERSIBLE VARIABLE VOLUME PUMP Filed Oct. 17, 1962 2 Sheets-Sheet lINVENTOR! ILIP HARTMANN T TORNEV June 8, 1965 P. HARTMANN REVERSIBLEVARIABLE VOLUME PUMP 2 Sheets-Sheet 2 Filed Oct. 17, 1962 PH ILIQ IZ XVGn IANN l 21 7 TO/PNEV United States Patent 3,187,676 REVERSELE VARKABLEVGLUME PUB E Phiiip Hartmann, Racine, Wis assignor to HartmannManufacturing (10., Racine, Wis a corporation of Wisconsin Filed0et.'17, 1962, Ser. No. 231,664 8 Claims. (Cl. 103-429) This inventionrelates to a reversible hydraulic pump.

Reversible hydraulic pumps are known in the art, and they generally havea construction which enables them to pump their hydraulic medium ineither directionthrough the pump though only one rotation of rotorrotation is employed. Thus upon movement of a porting ring which ofcourse encloses the rotor which is mounted on a fixed axis, thedirection of pumping the fluid through the pump housing is controlledsimply .by displacement of the port ring with respect to the fixedaxistof the rotor. Of course in these constructionsthere are problems ofmachining and assembling the pump to have it arranged so that the rotorcan be'rotated in only one'direction while the ring is sufiibindingforces on the parts and particularly on the movable port ring, and thusthe latter must be maintained free for its desired movement asmentioned.

It is accordingly a general object of this invention to provide animproved reversible pump which overcomes the problems of the heretoforeknown pumps of this type. D

In accomplishing this object, a pump of this invention is constructed sothat it is easily manufactured or machined in a manner which permits theseveral parts thereof to be assembled in adequate close tolerance sothat the parts can both move and operate as desired, and so that there3,137,6I Patented June 8, 1965 opposite sides thereof, but is alsouniform or symmetrical 7 with respect to the port ring in the directionof movement of the port ring so that the port ring cannot cock itselfand bind within the pump. a

Other objects and advantages will become apparent upon reading thefollowing description in light of the accompanying drawings whereiniFIG. 1 is a longitudinal sectional view througha preferred embodiment ofthis invention with a portion thereof broken away, and taken along theline 11 of FIG. 2.

. FIG. 2 is a sectional view taken along the line 2--2' of FIG. 1. 7 V

FIG. 3 is a sectional view taken along the line33 of FIG. 1.

The drawings show a reversible hydraulic pump generally having a housing10 with a cavity 11 therein. A floating or movable port ring 12 isdisposed Within the housing cavity 11, and it is important to note thatthe ring 12 is slidably related to guide members or pins 13. Also, theposition of the ring 12 determines the .quantity of fluid pumped so itis. a variable volume pump as Well as j a reversible one. The pins 13are snugly fitted into the housing It) in the circular openings'14 sothat the housing can support, the pins 13 in a fixed position. The upperends of the pins or guide members 13 also are shown to be in contactwith projections 16 of the housing 10, and

FIG. 3 particularly shows that the projection 16 is formed by :acontinuation of the housing bore 14so that an arcuatesurface 17 ispresented toward the outside surface 20 v to receive the forces appliedthereto by the fluid pressure.

I and the port ring 12 in a manner described later;-

will be only a very minimum or even negligible amount of fluid leakingat the interior of the pump.

Still another and'more specific object of this invention is to provide areversible hydraulic pump wherein the operating parts thereof need notbe in contact with the interior of the housing and thus the manufactureof the pump is simplified from that heretofore known.

Still another specific object of this invention is to provide areversible hydraulic pump wherein internal hydraulic pressures of a pumpare not effective to create undesirable or unbalanced forces on theoperating parts of the pump or to cause pump leakage, and also whereinthe hydraulic pressure is contained in the port ring so that the housingis not subjected to a high pressure, and therefore need not be designedfor high pressure.

A further object of this invention is to provide a IGVGYS', iblehydraulic pump of the vane type and with the vanes arranged so that amaximumpumping efficiency is attained regardless of the direction ofpumping through either of two fluidpassageways in the pump. Thus whilethe rotor is arranged to rotate in one direction only, but the pumpingis through either of the two fluid passageways in the pump, the pump,particularly through its vanes as To further support the port ring 12and control its posiis slidably disposed in a .cap 26 secured to the topof the housing 10 by bolts 27. Also, the housing 10 has an opening 28for reception of the stud 23 and movement of the latter along its axisas mentioned.

FIG. 2 shows the control block 24 to also be retained a by a side plate23 which is secured to the cap 26 by bolts, such as the bolt 29. and itsplate 28 present anrinter nal cavity 31 in which the block 24 is'slidable, and an eccentric 32 is received within a cavity 33 in theblock 24. A shaft 34 is integral with the eccentric 32 so that of courserotation of the shaft similarly rotates the eccentric 32, and, since theshaft 34 is fixedton roller bearings 36 to have a fixed axis ofrotation, theeccentric 32 will effect a camming action to displace theblock 24 and the stud 23 and likewise the port ring 12. V v

Thus the parts described, and including the movable parts justmentioned, present a control means for displacing the ring '12 withrespect to the support or guide members 13.

A rotor 37 is also disposed Within the housing 1%) on a fixed axis byvirtue of the roller bearings 38 supported in the 'housing 10. The rotorincludes the vane slotted portion 38, and the side plates 41, and thevanes. 42.

The latter are of course radially movably disposed within vane slots 43,and it 1 will also be noted that the vanes have 'oifset ends 44 whichpermit hydraulic fluid to get under the ends 44 and maintain the vanesradially No. 165,626, filed January 11, 1962, now US. Patent Inthismanner, the cap 26 No. 3,149,792. Thus, the vanes 42 havethe'chamfer shown on the radially outer ends thereof, and the rotorrotates in the counterclockwise direction in FIG. 1 toward the vanechamfer. --In thismanner no mechanical means are employed for retainingthe vanes radially outwardly as desired, but nevertheless they areretained simply by virtue of the pressure of the fluid being pumped,

and this feature therefore permits the rotor to rotate in one direction,but the pump discharge can be to either side of the rotor as will beexplained later.

It Will also be notedv and understood that bolts, such as the bolt 46,extend between the rotor plates 41 and through the rotor portion 39 tosecure the entire rotor assembly together. I

The port ring 12 has a circular bore 47 which receives the rotor 37, andrelieved pockets 48 are formed in the ring 12 to provide the fluidpassageway therein and are shaped as shown in dotted lines in' FIG. 2.This of course therefore permits'the vanes 42 to slide overthe surface47 defining the ring bore,'and to of course pump the fluid through thering 12. in the desired manner. Projected portions 49 are atrthe top andbottom. of the ,ring 12, intermediate the pockets 48; Thus, if the ring12is moved upwardly, then the ring surface 49 will be intangentialcontact with the circumference of the rotor 37, which if rotatedcounter-clockwise will create. high pressure dischargefto the left, allas viewed in. FIG. 1. Also, if the ring 12is lowered, the reverse is Vtrue. Vanes 421are plication and have the rearward projections 44 whichcause the vanes to'remain radially out at all time's. With the ringdown, the vane'in the position indicated A remains out since pressure"is under the projection 44 though only suction is to the front side ofthe-vane and under the radially inner end thereof. f i

It will of course alsobenoted' that the floating ring Thus when the pumpdischargeis to the left as viewed in FIG. 1, then the high pressureacting as shown'inFIG 3 of said patent ap-- A fluid can be urged againstthe check balls 67. Thus in the event that a pressure of, for instance,twenty pounds is applied in the passageway 71 and thus against the checkball 67, and the pressure in the passageway 62 and 63 in either event isless than the inlet pressure of twenty pounds, then of course thepassageway 62 or 63, whichever is below the twenty pound pressure andrained therefrom through the drain passageway 76 and passageway 77.

Of course it will also be noted that the housing 10 has end plates 78and 79 which are suitably attached to the housing to' render thelatter'fluid tight, and of course the cap or plate 78 alsosupports'thebearing 38. It will therefore be further noted thatthe rotor 37 isradially fixed with respect to the housing as the bearings 38 secure therotor in the housing so that the reversing "action of fluid-flow throughthe pump is provided simply by displacement of the floating port ring 12asdescribed.

It is therefore important toappreciate that the rotor '37 is symmetricalabout'both a vertical and a horizontal axis, as viewed in FIG. 1, andthus any'internal pressure created by fluid being pumpedby the rotorwillbe halon the ring and pockets 48 on the left 'of the ring, will L tendto urge the ring to the left, and this will of course create afluid-tight seal along the left line 51, and thus there will be noleakage. Also, the right side of the ring 12 maytend to move away fromthe pin 13, 'but this 'is of course only in the intakeof thepump wherethe fluid pressure is low and thus there is no leak-.

age problemat this point.

It will therefore be understood that the ring 12 has ports or fluidpassageways 52 and 53 which are of course fluid passageways 57 extendingfrom'flow communication locations with the passageways 54 and 56 to anopening or passageways .58' and 59 in 'a member 61 which is attachedtothe housing 10 in any conventional manner. Passageways 58 and 59 arethen of course in fluid-flow communication with passageways 62' and 63inthe member 61, and a conduit 64 is shown connected into the passageway62 for conducting fluid therethrough.

1 A flow regulator 66 is disposed within the member 61 and, includes twocheck balls 67' disposed in passageways 68 which are of course in flowcommunication with the passageway 62. and 63 separately. Compressionsprings 69 urge the check balls 67 into 'a'close d seating relation witha central passageway 71 which is in flow communication with thepassageways 68. Still further, a fluid inlet opening 72 extends from theexterior of the mem ber 61 to the circular groove 73 which'in turn is inthe passageways 74, and the passageway 71 where the anced in thevertical direction by its own pressure, applied against the port ring 12in an upward and a downward direction, and the'remaining forces createdby the fluid in the horizontal direction arebalanced .by the guidemembers 13, which of -courseare, in turn supported by the housing 10;Thus the balancing of the pump by virtue of its own pressure issimplified and an improvement in the art. I y

While a specific embodiment of this invention has been shown anddescribed, it should be obviousthat certain changes could be madetherein and the invention therefore should be determined only by pendedclaims;

What is claimed is: t

1; Agreversible ivariable volume pump comprising a housing and having achamber therein, a .portring movably dispo'sed'insaid chamber and spacedfrom said hous ing, a guide member fixedly mounted in said housing oneach of the opposite sides of saidport ring and extending across vsaidport ring in the direction of movement of the latter, said port ring andsaid guide members having mated ar cuate surfaces in sliding engagementfor guiding the movement of 'said port ring, said port ring havinga boretherein and two-fluid passageways therein-respectively extending throughsaid opposite sides and into fluid-flow communication with said bore andthrough said arcuate surfaces a rotor rotatably mounted in said housingon a fixed axis and disposed inside said port ring for moving fluidtherein, and each said arcuate surface of said guide members having afluid passageway extending therein "in separate fluid-flow communicationwith said passageways of said port ring for conducting fluid into andout of said port ringbore 'as determined by the position of said portring, I

2; A reversible variablevolume pump comprising a housing having achamber therein, a port ring movably disposed in said chamber and spacedfrom said housing, means on said housing and operatively interrelatedwith said port ring for moving the latter along a plane, guide ,membersfixedly mounted in said housing and disposed on opposite sides ofsaidportrring and eachextending across said port ring in a directionparallel to said plane to be in sliding engagement with said port ringfor guiding communication with said bore and through said arcuate thescope of the apsurfaces, a rotor rotatably mounted in said housing on afixed axis and inside said port ring for moving fluid therein, said portring bore being symmetrical in the direction of its movement for pumpingfluid to either of said opposite sides in response to rotation of saidrotor in only one direction and in accordance with the position of saidport ring, and each of said guide members having a fluid passagewayextending therein and through said arcuate surface and in separatefluid-flow communication with said passageways of said port ring forconducting fluid into and out of said port ring'bore as determined bythe position of said port ring.

3. A reversible variable volume pump comprising a housing having achamber therein, a port ring movably disposed in said chamber and spacedfrom said housing and having planular faces on axially opposite faces ofsaid port ring, guide members fixedly mounted in said housing onopposite sides of said port ring and extending across said port ring insliding engagement therewith for guiding the movement of said port ring,said port ring having a central bore therein and two fluid ports influid-flow communication with said bore on said opposite sides andexteriorly of said port ring, a rotor rotatably mounted in said housingon a fixed axis and inside said bore for moving fluid therein and havingplanular faces co-planular with said planular faces of said port ring,side plates removably attached to said planular faces of said rotor andextending beyond the limits thereof and being in sliding contact withsaid planular faces of said port ring, and each of said guide membershaving a fluid passageway extending therein in separate fluid-flowcommunication with said ports of said port ring for conducting fluidinto and out and in slding support of said port ring in the planestrans;

verse to said line of movement of said ring and said guide surfaces eachhaving a fluid passageway extending therethrough in separate fluid-flowcommunication with said ports for conducting fluid into and out of saidport ring bore as determined by the position of said port ring, saidport ring being symmetrical about both its axis on said line of movementand its axi transverse to said line of movement and with said port ringhaving a fluid pocket of the same dimensions on each side of said portsin the plane of rotor rotation and in fluid-flow communication with saidbore for directing fluid and balancing fluid forces acting on said portring in the planes parallel to said line of movement of said port ring.

5. A reversible variable volume pump comprising a housing having achamber therein, a port ring movably disposed in said chamber and spacedfrom said housing, circular guide members fixedly mounted in saidhousing on each of the diametrically opposite sides of said port ringand extending across said chamber and said port ring in the direction ofmovement of said port ring and with the latter including concavesurfaces conforming to and snugly abutting at least a part of thecircumference of said guide members for guiding the movement of saidport ring, said port ring having a bore therein and two fluid ports influid-flow communication with said bore and extending through saidconcave surfaces, a rotor rotatably mounted in said housing on a fixedaxis and disposed inside said port ring and having vanes thereon formoving fluid through said port ring, each of said guide members having afluid passageway extending therein in separate fluid-flow communicationwith said ports of said 6 port ring for conducting fluidinto and out ofsaid por ring bore according to the position of said port ring, saidport ring and said rotor being equal in axial length to have therespective ends thereof on common planes, and side plates attached tosaid ends of said. rotor and extending radially therebeyond and flankingsaid ends of said port ring in fluid-tight relation with said rotor andsaid port ring. 7

6. A reversible variable volume pump comprising a housing having achamber therein, a port ring movably disposed in-said chamber and spacedfrom said housing, means on said housing and operatively interrelatedwith said port ring for moving the latter along a line of movement,,saidportring having arcuately shaped opposite ,sides and a central bore andtwotfluid ports axially aligned on said opposite sides of said port ringand with the axis of said ports disposed transverse to said line ofmovement and with said ports being in fluid-flow communication with saidbore, arcuately shaped guide members fixedly mounted in said housing anddisposed to be fluid-tightly mated with said opposite sides of said portring and extending across said ports in sliding engagement with saidport ring for guiding the movement of said port ring, a rotor rotatablymounted in said housing on a fixed axis and inside said port ring andhaving vanes for moving fluid, said port ring having fluid pockets opento said rotor and adjacent said ports for fluid-pressure balancing saidport ring inthe' directions of movement of said port ring, side platesremovably attached to said rotor and extending in flanking relation withsaid port ring and being fluid tight with said rotor and said port ring,said port ring -being symmetrical with respect to said port axis forbalancing fluid pressure in said line of movement and for pumping fluidto either of said ports-in response to rota tion of said rotor in onlyone direction and in accordance with the position of said port ring, andeach of said guide members having'a fluid passageway extending thereinin separate fluid-flow communication with said ports of said port ringfor conducting fluid into and out of said port ring bore.

7. A reversible variable volume pump comprising a housing having achamber therein, a port ring movably disposed in said chamber and spacedfrom said housing, means on said housing for moving said port ring,guide members fixedly mounted in said housing on opposite sides of saidport ring and extending across said port ring in sliding engagementtherewith for guiding the movement of said port ring, said port ringhaving a central bore therein and two fluid ports in fluid-flowcommunication with said bore and axially aligned on said opposite sides,a rotor rotatably mounted in said housing on a fixed axis and insidesaid bore, vanes radially disposed on said rotor in sliding contact withthe'wall defining said bore and having a'projection on the radiallyouter ends thereof toward the rotationally trailing side of said vanesand in sliding cont-act with the wall of said bore to receive fluidpressure underneath said projection for urging said vanes radiallyoutwardly, side plates fluid-tightly and housing having a chambertherein, a port ring movably disposed in said chamber, said port ringhaving a bore therein and two fluid ports in fluid-flow communicationwith said bore and on diametrically opposite sides thereof coaxial withthe plane of said ring transverse to the line of movement of the latter,a rotor rotatably mounted in said housing on a fixed axis and disposedinside said port ring for moving fluid therein, said ring including twosurfaces of equal dimensions on said borethereof on diametricallyopposite sidesin the plane of movement of said ring for selectivesealing with said rotor upon displacement of said ring and said ringhaving fluid pressure balancing pockets extending between said surfacesand adjacent said ports and being of equal dimensiongguide surfaces insaid housing extending past said ports and having a fluid passagewayextending in each of said surfacesin separate fluid-flow communicationwith said ports for conducting fluid into and out of said port ring boreas determined by the position ofsaid port ring, said guide surfacesextending in planes parallelto said line of movement for receiving andcountering the force of fluid pres,-

sure between said ring and said rotor in the directions" toward saidsurfaces, vanes radially movably disposed on said rotor andincludingprojections extending to the'rotational-ly trailing sideof'said vanes and exposed to fluid pressure on the radially inwardsurface of said projections for urging .said vanes radially outwardlyagainst; said port a 8. ring, and side plates removably attached to saidrotor and extending beyond said vanes and flanking said port ring.

Reference's'Cited by the Examiner UNITED STATES PATENTS 2 Tucker et a1.-2 103-120 2,394,120 2/46 Tucker 103-120 2,955,542 10/60 Gaubatz 103-120r 3,008,423 11/61 Miller ...4 103-120 3,016,017 1/62 'Prendergast'103120 3,054,357" 9/62 McGill 103126 FOREIGN PATENTS 5 JOSEPH HBRANSON, JR;, Examiner.

1. A REVERSIBLE VARIABLE VOLUME PUMP COMPRISING A HOUSING AND HAVING ACHAMBER THEREIN, A PORT RING MOVABLY DISPOSED IN SAID CHAMBER AND SPACEDFROM SAID HOUSING, A GUIDE MEMBER FIXEDLY MOUNTED IN SAID HOUSING ONEACH OF THE OPPOSITE SIDES OF SAID PORT RING AND EXTENDING ACROSS SAIDPORT RING IN THE DIRECTION OF MOVEMENT OF THE LATTER, SAID PORT RING ANDSAID GUIDE MEMBERS HAVING MATED ARCUATE SURFACES IN SLIDING ENGAGEMENTFOR GUIDING THE MOVEMENT OF SAID PORT RING, SAID PORT RING HAVING A BORETHEREIN AND TWO FLUID PASSAGEWAYS THEREIN RESPECTIVELY EXTENDING THROUGHSAID OPPOSITE SIDES AND INTO FLUID-FLOW COMMUNICATION WITH SAID BORE ANDTHROUGH SAID ARCUATE SURFACES, A ROTOR ROTATABLY MOUNTED IN SAID HOUSINGON A FIXED AXIS AND DISPOSED INSIDE SAID PORT RING FOR MOVING FLUIDTHEREIN, AND EACH SAID ARCUATE SURFACE OF SAID GUIDE MEMBERS HAVING AFLUID PASSAGEWAY EXTENDING THEREIN IN SEPARATE FLUID-FLOW COMMUNICATIONWITH SAID PASSAGEWAYS OF SAID PORT RING FOR CONDUCTING FLUID INTO